Editing Germanium (section)

=== Other uses ===
[[File:Pet Flasche.JPG|thumb|upright|A [[polyethylene terephthalate|PET]] [[bottle]]|alt=Photo of a standard transparent plastic bottle.]]
Germanium dioxide is also used in [[catalyst]]s for [[polymerization]] in the production of [[polyethylene terephthalate]] (PET).<ref name="Thiele">{{cite journal |last=Thiele |first=Ulrich K. |date=2001 |title=The Current Status of Catalysis and Catalyst Development for the Industrial Process of Poly(ethylene terephthalate) Polycondensation |journal=International Journal of Polymeric Materials |volume=50 |issue=3 |pages=387–394 |doi=10.1080/00914030108035115 |s2cid=98758568}}</ref> The high brilliance of this polyester is especially favored for PET bottles marketed in Japan.<ref name="Thiele" /> In the United States, germanium is not used for polymerization catalysts.<ref name="usgs" />

Due to the similarity between silica (SiO<sub>2</sub>) and germanium dioxide (GeO<sub>2</sub>), the silica stationary phase in some [[gas chromatography]] columns can be replaced by GeO<sub>2</sub>.<ref>{{cite journal |title=Germania-Based, Sol-Gel Hybrid Organic-Inorganic Coatings for Capillary Microextraction and Gas Chromatography |last1=Fang |first1=Li |last2=Kulkarni |first2=Sameer |last3=Alhooshani |first3=Khalid |last4=Malik |first4=Abdul |journal=Anal. Chem. |volume=79 |issue=24 |pages=9441–9451 |date=2007 |doi=10.1021/ac071056f |pmid=17994707}}</ref>

In recent years germanium has seen increasing use in precious metal alloys. In [[sterling silver]] alloys, for instance, it reduces [[firescale]], increases tarnish resistance, and improves precipitation hardening. A tarnish-proof silver alloy trademarked [[Argentium sterling silver|Argentium]] contains 1.2% germanium.<ref name="usgs" />

[[Semiconductor detector#Germanium detectors|Semiconductor detectors]] made of single crystal high-purity germanium can precisely identify radiation sources—for example in airport security.<ref>{{cite web |title=Performance of Light-Weight, Battery-Operated, High Purity Germanium Detectors for Field Use |first1=Ronald |last1=Keyser |last2=Twomey |first2=Timothy |last3=Upp |first3=Daniel |url=http://www.ortec-online.com/papers/inmm_2003_keyser.pdf |access-date=2008-09-06 |publisher=Oak Ridge Technical Enterprise Corporation (ORTEC) |archive-url=https://web.archive.org/web/20071026162911/http://www.ortec-online.com/papers/inmm_2003_keyser.pdf |archive-date=October 26, 2007 |url-status=dead}}</ref> Germanium is useful for [[Crystal monochromator|monochromators]] for [[beamline]]s used in [[single crystal]] [[neutron scattering]] and [[Synchrotron light|synchrotron X-ray]] diffraction. The reflectivity has advantages over silicon in neutron and [[High energy X-rays|high energy X-ray]] applications.<ref>{{cite journal |doi=10.1142/S0218301396000062 |date=1996 |journal=International Journal of Modern Physics E |volume=5 |issue=1 |pages=131–151 |title=Optimization of Germanium for Neutron Diffractometers |bibcode=1996IJMPE...5..131A |last1=Ahmed |first1=F. U. |last2=Yunus |first2=S. M. |last3=Kamal |first3=I. |last4=Begum |first4=S. |last5=Khan |first5=Aysha A. |last6=Ahsan |first6=M. H. |last7=Ahmad |first7=A. A. Z.}}</ref> Crystals of high purity germanium are used in detectors for [[gamma spectroscopy]] and the search for [[dark matter]].<ref>{{cite journal |doi=10.1016/j.nuclphysa.2005.02.155 |title=Astrophysical constraints from gamma-ray spectroscopy |date=2006 |last1=Diehl |first1=R. |journal=Nuclear Physics A |volume=777 |issue=2006 |pages=70–97 |last2=Prantzos |first2=N. |last3=Vonballmoos |first3=P. |arxiv=astro-ph/0502324 |bibcode=2006NuPhA.777...70D |citeseerx=10.1.1.256.9318 |s2cid=2360391}}</ref> Germanium crystals are also used in X-ray spectrometers for the determination of phosphorus, chlorine and sulfur.<ref>Eugene P. Bertin (1970). ''Principles and practice of X-ray spectrometric analysis'', Chapter 5.4 – Analyzer crystals, Table 5.1, p. 123; Plenum Press</ref>

Germanium is emerging as an important material for [[spintronics]] and spin-based [[quantum computing]] applications. In 2010, researchers demonstrated room temperature spin transport<ref>{{Cite journal |last1=Shen |first1=C. |last2=Trypiniotis |first2=T. |last3=Lee |first3=K. Y. |last4=Holmes |first4=S. N. |last5=Mansell |first5=R. |last6=Husain |first6=M. |last7=Shah |first7=V. |last8=Li |first8=X. V. |last9=Kurebayashi |first9=H. |date=2010-10-18 |title=Spin transport in germanium at room temperature |journal=Applied Physics Letters |volume=97 |issue=16 |page=162104 |doi=10.1063/1.3505337 |issn=0003-6951 |bibcode=2010ApPhL..97p2104S |url=https://eprints.soton.ac.uk/271616/1/Gespin.pdf |access-date=2018-11-16 |archive-date=2017-09-22 |archive-url=https://web.archive.org/web/20170922180043/https://eprints.soton.ac.uk/271616/1/Gespin.pdf |url-status=live}}</ref> and more recently donor electron spins in germanium has been shown to have very long [[coherence time]]s.<ref>{{Cite journal |last1=Sigillito |first1=A. J. |last2=Jock |first2=R. M. |last3=Tyryshkin |first3=A. M. |last4=Beeman |first4=J. W. |last5=Haller |first5=E. E. |last6=Itoh |first6=K. M. |last7=Lyon |first7=S. A. |date=2015-12-07 |title=Electron Spin Coherence of Shallow Donors in Natural and Isotopically Enriched Germanium |journal=Physical Review Letters |volume=115 |issue=24 |pages=247601 |doi=10.1103/PhysRevLett.115.247601 |pmid=26705654 |arxiv=1506.05767 |bibcode=2015PhRvL.115x7601S |s2cid=13299377}}</ref>